Such entrance and exit devices are known per se in particular for passenger doors, but also for entrance ramps, sliding steps and suchlike on public transportation vehicles. These are often arranged in the region of the door frames or door portals above a passage opening. For example, pivot sliding doors are described in EP 10 409 79 A2 and EP 13 146 26 A1. The drives which are shown therein are therefore suitable in particular for pivot sliding doors, which carry out a pivoting and a lateral displacement during the opening and closing process. Also drive devices for purely rotating or pivoting doors, i.e. doors which do not carry out a lateral displacement, are generally arranged above or below the doors in the region of the door portal. DE 203 16 764 U1 describes the arrangement of a drive device in the upper region of the door portal.
A disadvantage in these drive devices is always that they require considerable structural space. It has also been found that the mounting and adjusting of such drive devices and doors is very time-consuming.
A drive device in particular for passenger doors which is of very compact construction is known from DE 20 2008 007 585 U1. By its narrow and elongate construction, it is possible to integrate the drive device into a rotary column of a passenger door. In addition to a saving of space, the accommodating of the drive unit directly in the rotary column also has several advantages with regard to maintenance and installation of the entire drive device. In addition to this is the fact that the drive device, through a special mounting, is largely kept free of stresses through movements of the vehicle, of the portal or of the rotary column.
However, a problem also exists in such compact drive systems in that when, in the opened or closed state, greater external forces are applied on, for example, the door leaves, very large forces are exerted via the lever arms of the door system onto the drive unit and the gear unit of the drive device. These forces occur in particular in the case of vandalism or during opening and closing processes in overcrowded vehicles and can even lead to damage to the drive or to the gear unit when initiated abruptly, e.g. on the opened door leaf.